How is the crown attached on a vintage Seamaster manual, caliber 610? Mine came off and I couldn't seem to thread it back on to the stem, but after several tries, it seemed to grab something (not sure what) and remain attached to the case and be able to wind again. When I had the crown in my hand I was so rattled about it coming off that I didn't look closely at the crown and it's post to see whether it was threaded or not.....Thanks for any help.
Crowns are threaded for the stem which is also threaded. It sounds like your threads could be damaged, you should take the watch to a watchmaker and have it looked at and the crown secured properly. It's not possible to tighten the crown to the stem properly by simply screwing it back in place. Rob